Iranian Journal of

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  Background and Objectives : Influenza is an acute, contagious, and zoonotic viral disease. It is caused by a virus of the Orthomyxoviridae family. This very infectious is caused by different subtypes of type A influenza virus in the poultry, turkey, and many other birds. In this study, the serum status of rural domestic poultry was investigated for influenza subtype H9N2.

 Methods: This cross sectional study was done from August to October in 2013 in Iranian villages through sampling domestic poultry. The sampling was accidental and was done based on the GIS 11-digit code. In each village, blood samples were taken from at least 28 birds from different species. Then, ELISA was used for screening followed by the HI test. A total of 397 villages and 11546 birds (10145 chickens, 1413 ducks, 397 turkeys, 10 pigeons, and 175 other species) were sampled.

  Results : Three hindered and forty nine (88%) out of 397 villages were positive on ELISA. In addition, 341 villages (86%) were positive and 56 (14%) were negative on the HI test for antibody titers. Also, among the considered variables, weather was a risk factor and the prevalence was significantly lower in villages near the rivers, lagoons and lakes (up to a radius of 3 Km).

  Conclusion: The high seroprevalence of influenza H9N2 in rural domestic poultry indicates that the disease is becoming endemic. As there is no eradication policy for influenza H9N2 in Iran, using effective vaccines can reduce the infection with influenza virus in domestic and rural poultry.

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Background and Objectives: Avian influenza (AI) is one of the most important respiratory diseases in the poultry industry that causes huge economic impacts and plays an important role in public health. H9N2 Avian Influenza Virus (H9N2 AIV) has a broad circulation and causes endemic infections in the poultry industry of the country.
 
Methods: A cohort study was conducted from July 2016 to November 2017 in broiler chicken farms of Qazvin Province, Iran to detect H9N2 AIV infection determinants in broiler chicken farms.
 
Results: Sixteen out of 34 units that were included in the study had positive PCR results. Some variables such as “type of fence around the unit”, “biosecurity”, “cooling system status”, “mean maternal antibody titers”, “location height”, “proximity to public traffic lanes” and “number of units within a radius of 1 km” had significant effects on the infection occurrence in poultry units according to univariate statistical analyses (P<0.05). However, only two of them (“biosecurity” and “cooling system status”) were statistically significant in multi-variable analyses (P<0.05).
 
Conclusion: Biosecurity measures should be implemented more seriously and strictly in broiler farms to reduce the impact of H9N2 AIV infection.